1. Field of the Invention
The present invention relates to electrically powered garden tools such as a power-operated hedge trimmer, an electrically powered grass shear and the like.
2. Description of the Prior Art
Disclosed in Japanese Patent Laid-open Publication Nos. 2007-075917 and 2010-094086 is an electrically powered hedge trimmer of the type which includes an electric motor mounted upright within an outer shell housing, a pair of relatively reciprocating shear blades assembled to be driven by operation of the motor through a crank mechanism provided within a lower portion of the outer shell housing, and a cooling fan assembled to be driven by operation of the motor for introducing outside air from an intake opening formed in an upper peripheral wall of the outer shell housing and for exhausting the sucked air from an opening laterally formed in a lower peripheral wall of the outer shell housing.
When the electric motor of the hedge trimmer is activated to impart reciprocal motion to the shear blades and to rotate the cooling fan, an operator is situated in an unpleasant condition caused by the blow of air exhausted laterally from the exhaust opening of the lower peripheral wall of the outer shell housing. The operator is also situated in an unpleasant condition caused by blow noises of the exhaust air and driving noises transmitted from the crank mechanism during reciprocal motion of the shear blades.
Disclosed in Japanese Patent Publication No. No. 2010-094086 is a hedge trimmer of the type which includes an electric motor mounted upright within a motor housing, a pair of relatively reciprocating shear blades assembled to be driven by operation of the motor through a crank mechanism provided within a lower portion of the motor housing, and a cooling fan assembled to be driven by the motor for introducing outside air from an intake opening formed in an upper peripheral wall of the motor housing and for exhausting the sucked air from an exhaust opening formed in a lower peripheral wall of the motor housing, and an outer shell housing enclosing the intake opening and exhaust opening of the motor housing.
When the electric motor of the hedge trimmer is activated to impart reciprocal motion to the shear blades and to rotate the cooling fan, the air exhausted from the lower opening of the motor housing blows out from the lower end opening of the outer shell housing through a space between the lower peripheral walls of the outer shell housing and motor housing. As the exhaust air from the motor housing blows out from the lower end opening of the outer shell housing, the exhaust air directly blowing against the operator is restrained. However, the exhaust air from the lower end opening of the outer shell housing blows against the lower end peripheral wall of the motor housing protruded toward the lower end opening of the outer shell housing and blows out obliquely in a side direction. Due to such blow of the exhaust air, it is unable to reduce blowing noises of the air exhausted from the lower end opening of the outer shell housing and to reduce driving noises caused by reciprocal motion of the shear blades.